TABLE OF CONTENTS 



CHAPTER I 



ORE DEPOSITS INTRODUCTION 1-23 



Definition, 1. Primary source of ores, 1-2. Enrichment of 

 ore bodies, 3. Causes of precipitation, 4. Mineral springs, 6. 

 Origin of cavities, 7. Faults, 9. Veins, 11. Richness of 

 veins, 14. Irregularities in veins, 14. Ribbon structure, 15. 

 Age of veins, 18. Classification of ore deposits, 18-20. 

 What constitutes a mine?, 20-23. 



CHAPTER II 



ORIGIN OP ORE DEPOSITS 24-51 



Meteoric origin, 24. Number of meteorites, 24. Content of 

 meteorites, 25. Segregation, 25-29. Pneumatolysis, 29-33. 

 Hydatogenesis, 33-35. Metasomasis, 35-41. Precipitation, 

 41-42. Metamorphism, 42-46. Secondary changes, 46-47. 

 Detrital deposits, 47-51. 



CHAPTER III 



PRECIOUS METALS GOLD, SILVER, PLATINUM 52-109 



Ores of gold, 52. Character of the ore bodies, 56. Geograph- 

 ical distribution, 60-83. Appalachian belt, 60. Black Hills 

 district, 62. Cordilleran region, 66. Sierra region, 72. 

 Pacific Coast region, 75. Alaskan field, 77. Placers, 79. 

 Placers classified, 81. Porcupine, 83. Geological horizon, 83. 

 Placer mining, 84. Methods of extraction, 86-89. Uses, 89. 

 Silver, 89. Character of the ore bodies, 91-97. Geographical 

 distribution, 97. Geological horizon, 98. Methods of extrac- 

 tion, 98-102. Uses, 102. Platinum, 102. Methods of extrac- 

 tion, 104. Uses, 104. Rare precious metals, 106-108. Losses 

 of the precious metals, 108-109. 



LEAD, MERCURY 110-130 



Ores of lead, 110. Origin of the ores, 111. Character of the 

 ore bodies, 111-114. Geographical distribution, 114-122. 

 Appalachian district, 114. Mississippi River belt, 115. 

 Cordilleran district, 117. Geological horizon, 122. Methods 

 of extraction, 122-123. Uses, 123-126. Ores of mercury, 1 iv,. 



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